I have a pretty bad situation at my place. I have a leaky shower faucet which has gone from drips to a steady stream. I calculated the flow at .3 gallons per minute. My very old home has no private shut off valve for the water. I tried to shut the water off at the meter, but the valve was very tough and I didn't want to force it, break something, and be liable.

I've noticed that the water coming out of the faucet is pretty hot. So, I tried shutting off the valve supplying cold water to my heater. The amount of water leaking from the bathroom faucet reduced significantly. Is it safe to simply shut off the cold water supply to my gas heater or will it cause problems with pressure? Will water come out of the pressure relief valve at some point?

This is a temporary measure until I can have the water shut off by the water company or plumber. For now, I've left it on.

4 Answers
4

If you have no separate shut off valve you should wait till the local water authority can come and temporarily shut off the water at the meter (which is presumably near the street).

I see no problem with shutting off the water supply to the water heater as a short term measure to curb the water waste from the leaking faucet in the shower. It would be a good idea to turn off the water heater during the time that the water supply is turned off.

After you turn the water supply back on the only issue you will have with the water heater is that some air could have fed back into the tank. All you have to do is to open the hot water valves in several of your sinks and let them run for a short while until the water runs clear without any bubbles or spitting coming out of the faucets.

Cant hurt the heater at all and no need to shut gas or electricity off to the HWS either as it's always full and only delivers you hot water by way of you opening hot tap and cold water entering bottom of tank forcing hot out. While you have hot water turned off why dont you replace the shower washer too? You can find out how simple to do on utube.

It is always a good idea to shut off the electricity or gas to a disconnected water heater. Without a water supply, what if the water leaked out? When it tries to heat, will will damage itself and possibly become a safety hazard.
– wallykJul 5 '14 at 4:14

1

I agree - if the heater did drain having it be on would be very bad indeed. It's never good advice to suggest NOT taking simple safety measures.
– The Evil GreeboJul 8 '14 at 12:02

Last time our hot water sprang a leak, the plumber wisely put in a cutoff valve right in front of the replacement water heater. We always turn it off when we go out of town (and the washing machine hose lines too), and never had an issue. As others noted, it would be safest to cut the power to the water heater if turned off for an extended period.

Normally but also depending on the age of the home there is a cold water shutoff behind the tub/shower handle assembly. Remove the handle usually a Phillip screw holds it on. Next remove round lock ring which is threaded on using channel lock pliers being careful not to deform the ring. Remove large round silver plate. You will see a round shutoff that has a slot for a standard screw driver. Turn to the right until it stops. Often you have to put pliers on the screw driver handle to help get it started. Turn off H/W at the H/W heater.Water is now off and remove the nut that holds the valve cartridge in place. Remove cartridge and repair or replace. Reverse procedure when done. There is variance on different brands but usually shutoff in the wall is the same. You might notice the same shutoff at your washing machine which turns off cold water to machine the same way the tub shuts off. I left out plumbing terms as they really don't matter. Remember to turn H/West back on.

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